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This chapter is from the book

This chapter is from the book

Using the Layer Mask Feature

A layer mask does something a little more substantial and dramatic than the name suggests. When you put a layer into Layer Mask mode, you can erase and restore image areas using selection or painting tools, but none of the changes are permanent. You can take a few minutes to refine the edge of an object on a layer, save the file, and open it up in a week, and still the changes you've made are proposed ones—nothing you see is permanent until you remove (apply) the layer mask. Let's get to the example of the layer mask, the dart, and the 15ball in the Pocket image.

Creating a Unique Composition Through Layers

You need to do two things to get the dart looking as though it was thrown at the 15ball by a small explosion. First, the dart needs to be on the top layer. Next, you need to remove part of the dart's tip and part of its shadow, combine the two dart pieces, and position them over the 15ball.

That's the plot. Let's get hatching...

Pinning Down a 15ball

  1. Drag the Dart layer title on the Layers palette to the top of the individual layers, as shown in item 1 of Figure 4.7. Or, if you remember the key commands for this, press Ctrl()+] (right bracket) until you can see the Dart title above the 15ball title.

  2. Move the dart closer to the 15ball by using the Move tool to drag the Dart layer, as shown in item 2 of Figure 4.7.

Figure 4.7Figure 4.7 The dart should be in front of the 15ball, and the two objects should be close to one another.

  1. Zoom in (Ctrl()+plus sign) so that you have a good view of the tip of the dart, and place that dart tip on the upper left of the pool ball. As you can see in Figure 4.8 a 100% viewing resolution does the trick. Now, click the Layer Mask icon with the Dart layer as the active layer. Weird stuff is going to happen when you go to apply the Paintbrush tool and the foreground color!

Figure 4.8Figure 4.8 When a layer's layer mask is in place, you are editing the visibility of areas; you are not moving or painting them.

  1. Click the Swap foreground/background colors icon if necessary to make black the current editing color. The Swap icon looks like a bent, two-headed arrow; you'll find it to the upper right of the color selection boxes on the toolbox. Choose the Paintbrush tool, and then right-click (Macintosh: hold Ctrl and click) to produce the Brushes palette over your work. Click the 19-pixel tip (this is the default palette of tips from which you're working), and press Enter to make your choice—and make the floating palette disappear. Drag the Paintbrush cursor over the tip of the dart, shortening the tip by about 50%. Do the same to the tip on the shadow of the dart.

  2. Black hides objects on a layer, and applying white restores the hidden areas. So if you goof, press X to swap foreground and background default colors, and restore what you wiped out.

  3. 5When your editing is finished (it should look pretty much like item 1 in Figure 4.9), drag the right thumbnail on the Dart layer title into the trash icon. Make sure it's the right side one you're trashing—this is the layer mask thumbnail (see item 2 in Figure 4.9). If you drag the left thumbnail into the trash, you delete the entire layer.

Figure 4.9Figure 4.9 Dragging the layer mask thumbnail into the trash means that you're serious about what you've painted to hide, and you want to permanently delete the hidden areas from the file.

  1. Next, the "last chance" attention box pops up (see Figure 4.10). When you trash a layer mask, Photoshop asks you whether you want to Apply the mask (permanently deleting hidden image areas), Cancel (think twice about trashing the hidden areas), or Discard (throw away your masking work and return everything to the way it was).

    Go for it. Click Apply with a swift, definitive keystroke.

Figure 4.10Figure 4.10 What a polite program!

  1. As you've probably noticed, there's a gap now between where the shadow of the dart ends and where the dart tip begins. This is a tad unrealistic, no? Press Ctrl()+S at this point, keep the image and Photoshop open, and we'll show you a trick in the following section for the precise union of dart and shadow.

There was a term a long time ago for what Adobe used to call an image area that was floating on top of the current editing layer. The name was floating selection. Adobe has dropped the term in recent versions and doesn't even tell you what's going on when you float an image area; however, that's okay. In the next section, we are going to show you how to create a floating selection and make it work for you.

Floating and Aligning the Dart with Its Shadow

As of version 4 of Photoshop, selection tools were redesigned to create selections, but they could not move the contents of the selection. Now the Move tool takes care of such feats as moving image areas on layers.

But by using a shortcut key and the arrow keys on your keyboard, you define a pretty broad selection around the dart and still place it precisely where you want it in the image.

Let's try out a new technique:

Finishing the Weird Composition

  1. With Dart as the target layer (I think there is an unintentional pun in there someplace), choose the plain Lasso tool, and drag a selection marquee around the dart, as shown in Figure 4.11. Be careful not to select any of the dart shadow.

Figure 4.11Figure 4.11 The selection might seem broad, but in reality, you are only selecting the non-transparent pixels on the layer—the dart.

  1. With the Lasso tool still chosen (and Feathering made 0px on the Options bar), place it inside the selection marquee and then hold Ctrl(). The cursor turns into a tiny Move tool with a pair of scissors hanging off of it. This means that if you move the marquee right now, the action will cut the selected area's contents from the layer. Nothing but transparency surrounds the dart, so this action is not destructive—and the dart selection is now hovering above the Dart layer.

  2. While holding the Ctrl() key, press the down- and right-arrow keys until the dart meets the tip of its shadow, as shown in Figure 4.12. You'll notice also that as soon as the marquee selection is moved, the marquee changes shape to conform to the non-transparent areas within the selection. This is a nice visual confirmation that you are moving the right thing on a layer.

Figure 4.12Figure 4.12 Hold Ctrl() and then use the keyboard arrow keys to nudge the selection toward the tip of the shadow.


Add Power to Your Keypress Just in case "power-nudging" sounds like fun to you, let us tell you what it is. You can hold Shift while you press the arrow keys to nudge a selection by 10 pixels instead of by one. This makes your fingers all twisted, but it can save time when you need coarse movement editing, followed by precise movements.

  1. Press Ctrl()+D to deselect the marquee, use the Move tool to reposition the dart so that it looks like it's piercing the 15ball, and you're done! In Figure 4.13, you can see the finished piece. I'm going to frame my copy and put it in the game room (right next to the my dreams).

  2. Keep Photoshop open, save the Pocket image, and keep it open, too.

Figure 4.13Figure 4.13 Reality is what you make it in Photoshop.

For the super fussy-at-heart, there is a mistake in the finished dart and pool ball image—in the shadow of the dart. Right now, the shadow extends in a linear fashion away from the dart tip, when, in reality, if a dart happened to get stuck in a pool ball, the shadow on the pool ball would be curved, and then it would be linear as soon as the shadow hits the table top.

You know what? Who's going to notice? I am exceptionally nit-picky on aspects of photorealism in Photoshop pieces, but this is one inaccuracy that you can afford to let go. Why? Because the shadow of the dart is at such a steep angle that it is severely distorted, and the average viewer will not notice that the shaded part of the pool ball doesn't shade it with an arc.

The sub-lesson here is that if you create an image that is dramatic and striking and appealing and all that, most viewers will skip over the small flaws.

Coming attractions: You're going to use an Adjustment Layer to enhance the tones in the Pocket image.

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